Electrolysis cell having conductive polymer electrodes and method of electrolysis

ABSTRACT

A method and apparatus are provided for performing electrolysis with an electrolysis cell. The cell includes an anode electrode and a cathode electrode. At least one of the anode electrode or the cathode electrode is at least partially formed of conductive polymer.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is based on and claims the benefit of thefollowing applications:

-   1) U.S. Provisional Patent Appln. No. 61/074,059, filed Jun. 19,    2008, entitled ELECTROLYSIS CELL HAVING CONDUCTIVE POLYMER    ELECTRODES AND METHOD OF ELECTROLYSIS;-   2) U.S. Provisional Patent Appln. No. 61/077,001, filed Jun. 30,    2008, entitled HAND-HELD SPRAY BOTTLE ELECTROLYSIS CELL AND DC-DC    CONVERTER;-   3) U.S. Provisional Patent Appln. No. 61/077,005, filed Jun. 30,    2008, entitled ELECTROLYSIS CELL HAVING ELECTRODES WITH    VARIOUS-SIZED/SHAPED APERTURES;-   4) U.S. Provisional Patent Appln. No. 61/083,046, filed Jul. 23,    2008, entitled ELECTROLYSIS DE-SCALING METHOD WITH CONSTANT OUTPUT;-   5) U.S. Provisional Patent Appln. No. 61/084,460, filed Jul. 29,    2008, entitled TUBULAR ELECTROLYSIS CELL AND CORRESPONDING METHOD;    and-   6) U.S. Provisional Patent Appln. No. 61/092,586, filed Aug. 28,    2008, entitled APPARATUS HAVING ELECTROLYSIS CELL AND INDICATOR    LIGHT ILLUMINATING THROUGH LIQUID;    the contents of which are hereby incorporated by reference in their    entirety.

FIELD OF THE DISCLOSURE

The present disclosure relates to electrochemical activation of fluidsand, more particularly, to electrolysis cells and corresponding methods.

BACKGROUND

Electrolysis cells are used in a variety of different applications forchanging one or more characteristics of a fluid. For example,electrolysis cells have been used in cleaning/sanitizing applications,medical industries, and semiconductor manufacturing processes.Electrolysis cells have also been used in a variety of otherapplications and have had different configurations.

For cleaning/sanitizing applications, electrolysis cells are used tocreate anolyte electrochemically activated (EA) liquid and catholyte EAliquid. Anolyte EA liquids have known sanitizing properties, andcatholyte EA liquids have known cleaning properties. Examples ofcleaning and/or sanitizing systems are disclosed in Field et al. U.S.Publication No. 2007/0186368 A1, published Aug. 16, 2007.

SUMMARY

An aspect of the disclosure relates to an electrolysis cell. The cellincludes an anode electrode and a cathode electrode. At least one of theanode electrode or the cathode electrode is at least partially formed ofconductive polymer.

Another aspect of the disclosure relates to a hand-held spray bottle.The bottle includes a liquid reservoir, a liquid outlet and anelectrolysis cell carried by the bottle and fluidically coupled betweenthe reservoir and the liquid outlet. The electrolysis cell has an anodeelectrode and a cathode electrode. At least one of the anode electrodeor the cathode electrode is at least partially formed of conductivepolymer. The bottle further includes a switch actuated between first andsecond states by a hand trigger, wherein the switch energizes theelectrolysis cell in the first state and de-energizes the electrolysiscell in the second state.

Another aspect of the disclosure relates to a method, which includeselectrolyzing a liquid using an electrolysis cell having at least oneconductive polymer electrode.

For example, the method includes the steps of: introducing a first partof the liquid into a first electrolysis chamber comprising a firstelectrode; introducing a second part of the liquid into a secondelectrolysis chamber comprising a second electrode, wherein the secondelectrolysis chamber is separated from the first electrolysis chamber byan ion selective membrane and wherein at least one of the first orsecond electrodes includes a conductive polymer; and applying a voltageacross the first and second electrodes to electrochemically activate thefirst and second parts of the liquid.

This Summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used as an aid in determining the scope of the claimed subjectmatter. The claimed subject matter is not limited to implementationsthat solve any or all disadvantages noted in the background.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a simplified, schematic diagram of a hand-held spray bottleaccording to an exemplary aspect of the present disclosure.

FIG. 2 illustrates an example of an electrolysis cell having anion-selective membrane.

FIG. 3 illustrates an electrolysis cell having no ion-selective membraneaccording to a further example of the disclosure.

FIG. 4A is a fragmentary view of a conductive polymer electrode having aplurality of rectilinear apertures in a regular grid pattern accordingto an aspect of the disclosure.

FIG. 4B is a fragmentary view of a conductive polymer electrode having aplurality of curvilinear apertures of different sizes in a regular gridpattern according to another example.

FIG. 4C is a fragmentary view of a conductive polymer electrode having aplurality of irregular and regular shaped apertures having a variety ofdifferent shapes and sizes according to another example.

FIG. 5 illustrates an example of an electrolysis cell having a tubularshape according to one illustrative example.

FIG. 6 is a waveform diagram illustrating the voltage pattern applied tothe anode and cathode according to an exemplary aspect of the presentdisclosure.

FIG. 7 is a block diagram of a system having an indicator according toan embodiment of the disclosure, which can be incorporated into any ofthe embodiments disclosed herein, for example.

FIG. 8A is a perspective view of a spray bottle having an indicatorlight that illuminates through liquid carried by the bottle.

FIG. 8B is a perspective view of a spray bottle having an indicatorlight that illuminates through liquid carried by the bottle, accordingto an alternative embodiment of the disclosure.

FIG. 8C is a rear, perspective view of a head of the bottle shown inFIG. 8B.

FIGS. 9A and 9B are perspective views of a left-hand side housing, andFIG. 9C is a perspective view of a right-hand side housing of the bottleshown in FIG. 8B.

FIG. 10 illustrates various components installed in the left-hand sidehousing.

FIGS. 11A and 11B illustrate a liquid container carried by the bottleshown in FIG. 8B.

FIG. 12A illustrates a fragmentary, close-up view of a pump/cellassembly installed in a barrel of the housing.

FIG. 12B is a perspective view of the pump/cell assembly removed fromthe housing.

FIG. 12C is a bottom, perspective view of the pump/cell assembly withthe trigger removed.

FIG. 13 illustrates an exploded, perspective view of a mounting bracketof the assembly shown in FIGS. 12A-12C.

FIGS. 14A and 14B are perspective views of a trigger of the bottle shownin FIG. 8B.

FIGS. 15A and 15B are perspective views of a trigger boot, whichoverlies the trigger.

FIG. 16A illustrates lower compartments of a housing half in greaterdetail.

FIG. 16B illustrates a circuit board and batteries mounted within thecompartments shown in FIG. 16A.

FIG. 17 is a perspective view of a mobile cleaning machine, whichimplements an electrolysis cell according to an example of the presentdisclosure.

FIG. 18 is a simplified block diagram of an electrolysis cell that ismounted to a platform according to another embodiment.

FIG. 19 is a perspective view of an all-surface cleaner according toanother embodiment of the disclosure.

FIG. 20 is a block diagram illustrating a control circuit forcontrolling the various components within the hand-held spray bottleshown in FIGS. 8-16 according to an illustrating example of thedisclosure.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

An aspect of the present disclosure is directed to a method andapparatus for electrolyzing liquids.

1. Hand-Held Spray Bottle

Electrolysis cells can be used in a variety of different applicationsand housed in a variety of different types of apparatus, which can behand-held, mobile, immobile, wall-mounted, motorized or non-motorizedcleaning/sanitizing vehicle, wheeled, etc, for example. In this example,an electrolysis cell is incorporated in a hand-held spray bottle.

FIG. 1 is a simplified, schematic diagram of a hand-held spray bottle 10according to an exemplary aspect of the present disclosure. Spray bottle10 includes a reservoir 12 for containing a liquid to be treated andthen dispensed through a nozzle 14. In an example, the liquid to betreated includes an aqueous composition, such as regular tap water.

Spray bottle 10 further includes an inlet filter 16, one or moreelectrolysis cells 18, tubes 20 and 22, pump 24, actuator 26, switch 28,circuit board and control electronics 30 and batteries 32. Although notshown in FIG. 1, tubes 20 and 22 may be housed within a neck and barrel,respectively of bottle 10, for example. A cap 34 seals reservoir 12around the neck of bottle 10. Batteries 32 can include disposablebatteries and/or rechargeable batteries, for example, and provideelectrical power to electrolysis cell 18 and pump 24 when energized bycircuit board and control electronics 30.

In the example shown in FIG. 1, actuator 26 is a trigger-style actuator,which actuates momentary switch 28 between open and closed states. Forexample, when the user “squeezes” the hand trigger to a squeezed state,the trigger actuates the switch into the closed state. When the userreleases the hand trigger, trigger actuates the switch into the openstate. However, actuator 26 can have other styles in alternativeembodiments and can be eliminated in further embodiments. In embodimentsthat lack a separate actuator, switch 28 can be actuated directly by theuser. When switch 28 is in the open, non-conducting state, controlelectronics 30 de-energizes electrolysis cell 18 and pump 24. Whenswitch 28 is in the closed, conducting state, control electronics 30energizes electrolysis cell 18 and pump 24. Pump 24 draws liquid fromreservoir 12 through filter 16, electrolysis cell 18, and tube 20 andforces the liquid out tube 22 and nozzle 14. Depending on the sprayer,nozzle 14 may or may not be adjustable, so as to select betweensquirting a stream, aerosolizing a mist, or dispensing a spray, forexample.

Switch 28, itself, can have any suitable actuator type, such as apush-button switch as shown in FIG. 1, a toggle, a rocker, anymechanical linkage, and/or any non-mechanical sensor such as capacitive,resistive plastic, thermal, inductive, etc. Switch 28 can have anysuitable contact arrangement, such as momenary, single-pole singlethrow, etc.

In an alternative embodiment, pump 24 is replaced with a mechanicalpump, such as a hand-triggered positive displacement pump, whereinactuator trigger 26 acts directly on the pump by mechanical action. Inthis embodiment, switch 28 could be separately actuated from the pump24, such as a power switch, to energize electrolysis cell 18. In afurther embodiment, batteries 32 are eliminated and power is deliveredto spray bottle 10 from an external source, such as through a powercord, plug, and/or contact terminals.

The arrangement shown in FIG. 1 is provided merely as a non-limitingexample. Spray bottle 10 can have any other structural and/or functionalarrangement. For example, pump 24 can be located downstream of cell 18,as shown in FIG. 1, or upstream of cell 18 with respect to the directionof fluid flow from reservoir 12 to nozzle 14.

As described in more detail below, the spray bottle contains a liquid tobe sprayed on a surface to be cleaned and/or sanitized. In onenon-limiting example, electrolysis cell 18 converts the liquid to ananolyte EA liquid and a catholyte EA liquid prior to being dispensedfrom the bottle as an output spray. The anolyte and catholyte EA liquidscan be dispensed as a combined mixture or as separate spray outputs,such as through separate tubes and/or nozzles. In the embodiment shownin FIG. 1, the anolyte and catholyte EA liquids are dispensed as acombined mixture. With a small and intermittent output flow rateprovided the spray bottle, electrolysis cell 18 can have a small packageand be powered by batteries carried by the package or spray bottle, forexample.

2. Electrolysis Cells

An electrolysis cell includes any fluid treatment cell that is adaptedto apply an electric field across the fluid between at least one anodeelectrode and at least one cathode electrode. An electrolysis cell canhave any suitable number of electrodes, any suitable number of chambersfor containing the fluid, and any suitable number of fluid inputs andfluid outputs. The cell can be adapted to treat any fluid (such as aliquid or gas-liquid combination). The cell can include one or moreion-selective membranes between the anode and cathode or can beconfigured without any ion selective membranes. An electrolysis cellhaving an ion-selective membrane is referred to herein as a “functionalgenerator”.

Electrolysis cells can be used in a variety of different applicationsand can have a variety of different structures, such as but not limitedto a spray bottle as discussed with reference to FIG. 1, and/or thestructures disclosed in Field et al. U.S. Patent Publication No.2007/0186368, published Aug. 16, 2007. Thus, although various elementsand processes relating to electrolysis are described herein relative tothe context of a spray bottle, these elements and processes can beapplied to, and incorporated in, other, non-spray bottle applications.

3. Electrolysis Cell Having a Membrane 3.1 Cell Structure

FIG. 2 is a schematic diagram illustrating an example of an electrolysiscell 50 that can be used in the spray bottle shown in FIG. 1, forexample. Electrolysis cell 50 and which receives liquid to be treatedfrom a liquid source 52. Liquid source 52 can include a tank or othersolution reservoir, such as reservoir 12 in FIG. 1, or can include afitting or other inlet for receiving a liquid from an external source.

Cell 50 has one or more anode chambers 54 and one or more cathodechambers 56 (known as reaction chambers), which are separated by an ionexchange membrane 58, such as a cation or anion exchange membrane. Oneor more anode electrodes 60 and cathode electrodes 62 (one of eachelectrode shown) are disposed in each anode chamber 54 and each cathodechamber 56, respectively. The anode and cathode electrodes 60, 62 can bemade from any suitable material, such as a conductive polymer, titaniumand/or titanium coated with a precious metal, such as platinum, or anyother suitable electrode material. In one example, at least one of theanode or cathode is at least partially or wholly made from a conductivepolymer. The electrodes and respective chambers can have any suitableshape and construction. For example, the electrodes can be flat plates,coaxial plates, rods, or a combination thereof. Each electrode can have,for example, a solid construction or can have one or more apertures. Inone example, each electrode is formed as a mesh. In addition, multiplecells 50 can be coupled in series or in parallel with one another, forexample.

The electrodes 60, 62 are electrically connected to opposite terminalsof a conventional power supply (not shown). Ion exchange membrane 58 islocated between electrodes 60 and 62. The power supply can provide aconstant DC output voltage, a pulsed or otherwise modulated DC outputvoltage, and/or a pulsed or otherwise modulated AC output voltage to theanode and cathode electrodes. The power supply can have any suitableoutput voltage level, current level, duty cycle or waveform.

For example in one embodiment, the power supply applies the voltagesupplied to the plates at a relative steady state. The power supply(and/or control electronics) includes a DC/DC converter that uses apulse-width modulation (PWM) control scheme to control voltage andcurrent output. Other types of power supplies can also be used, whichcan be pulsed or not pulsed and at other voltage and power ranges. Theparameters are application-specific.

During operation, feed water (or other liquid to be treated) is suppliedfrom source 52 to both anode chamber 54 and cathode chamber 56. In thecase of a cation exchange membrane, upon application of a DC voltagepotential across anode 60 and cathode 62, such as a voltage in a rangeof about 5 Volts (V) to about 28V, cations originally present in theanode chamber 54 move across the ion-exchange membrane 58 towardscathode 62 while anions in anode chamber 54 move towards anode 60.However, anions present in cathode chamber 56 are not able to passthrough the cation-exchange membrane, and therefore remain confinedwithin cathode chamber 56.

As a result, cell 50 electrochemically activates the feed water by atleast partially utilizing electrolysis and produceselectrochemically-activated water in the form of an acidic anolytecomposition 70 and a basic catholyte composition 72.

If desired, the anolyte and catholyte can be generated in differentratios to one another through modifications to the structure of theelectrolysis cell, for example. For example, the cell can be configuredto produce a greater volume of catholyte than anolyte if the primaryfunction of the EA water is cleaning. Alternatively, for example, thecell can be configured to produce a greater volume of anolyte thancatholyte if the primary function of the EA water is sanitizing. Also,the concentrations of reactive species in each can be varied.

For example, the cell can have a 3:2 ratio of cathode plates to anodeplates for producing a greater volume of catholyte than anolyte. Eachcathode plate is separated from a respective anode plate by a respectiveion exchange membrane. Thus, there are three cathode chambers for twoanode chambers. This configuration produces roughly 60% catholyte to 40%anolyte. Other ratios can also be used.

3.2 Example Reactions

In addition, water molecules in contact with anode 60 areelectrochemically oxidized to oxygen (O₂) and hydrogen ions (H⁺) in theanode chamber 54 while water molecules in contact with the cathode 62are electrochemically reduced to hydrogen gas (H₂) and hydroxyl ions(OH⁻) in the cathode chamber 56. The hydrogen ions in the anode chamber54 are allowed to pass through the cation-exchange membrane 58 into thecathode chamber 56 where the hydrogen ions are reduced to hydrogen gaswhile the oxygen gas in the anode chamber 54 oxygenates the feed waterto form the anolyte 70. Furthermore, since regular tap water typicallyincludes sodium chloride and/or other chlorides, the anode 60 oxidizesthe chlorides present to form chlorine gas. As a result, a substantialamount of chlorine is produced and the pH of the anolyte composition 70becomes increasingly acidic over time.

As noted, water molecules in contact with the cathode 62 areelectrochemically reduced to hydrogen gas and hydroxyl ions (OH⁻) whilecations in the anode chamber 54 pass through the cation-exchangemembrane 58 into the cathode chamber 56 when the voltage potential isapplied. These cations are available to ionically associate with thehydroxyl ions produced at the cathode 62, while hydrogen gas bubblesform in the liquid. A substantial amount of hydroxyl ions accumulatesover time in the cathode chamber 56 and reacts with cations to formbasic hydroxides. In addition, the hydroxides remain confined to thecathode chamber 56 since the cation-exchange membrane does not allow thenegatively charged hydroxyl ions pass through the cation-exchangemembrane. Consequently, a substantial amount of hydroxides is producedin the cathode chamber 56, and the pH of the catholyte composition 72becomes increasingly alkaline over time.

The electrolysis process in the functional generator 50 allowconcentration of reactive species and the formation of metastable ionsand radicals in the anode chamber 54 and cathode chamber 56.

The electrochemical activation process typically occurs by eitherelectron withdrawal (at anode 60) or electron introduction (at cathode62), which leads to alteration of physiochemical (including structural,energetic and catalytic) properties of the feed water. It is believedthat the feed water (anolyte or catholyte) gets activated in theimmediate proximity of the electrode surface where the electric fieldintensity can reach a very high level. This area can be referred to asan electric double layer (EDL).

While the electrochemical activation process continues, the waterdipoles generally align with the field, and a proportion of the hydrogenbonds of the water molecules consequentially break. Furthermore,singly-linked hydrogen atoms bind to the metal atoms (e.g., platinumatoms) at cathode electrode 62, and single-linked oxygen atoms bind tothe metal atoms (e.g., platinum atoms) at the anode electrode 60. Thesebound atoms diffuse around in two dimensions on the surfaces of therespective electrodes until they take part in further reactions. Otheratoms and polyatomic groups may also bind similarly to the surfaces ofanode electrode 60 and cathode electrode 62, and may also subsequentlyundergo reactions. Molecules such as oxygen (O₂) and hydrogen (H₂)produced at the surfaces may enter small cavities in the liquid phase ofthe water (i.e., bubbles) as gases and/or may become solvated by theliquid phase of the water. These gas-phase bubbles are thereby dispersedor otherwise suspended throughout the liquid phase of the feed water.

The sizes of the gas-phase bubbles may vary depending on a variety offactors, such as the pressure applied to the feed water, the compositionof the salts and other compounds in the feed water, and the extent ofthe electrochemical activation. Accordingly, the gas-phase bubbles mayhave a variety of different sizes, including, but not limited tomacrobubbles, microbubbles, nanobubbles, and mixtures thereof. Inembodiments including macrobubbles, examples of suitable average bubblediameters for the generated bubbles include diameters ranging from about500 micrometers to about one millimeter. In embodiments includingmicrobubbles, examples of suitable average bubble diameters for thegenerated bubbles include diameters ranging from about one micrometer toless than about 500 micrometers. In embodiments including nanobubbles,examples of suitable average bubble diameters for the generated bubblesinclude diameters less than about one micrometer, with particularlysuitable average bubble diameters including diameters less than about500 nanometers, and with even more particularly suitable average bubblediameters including diameters less than about 100 nanometers.

Surface tension at a gas-liquid interface is produced by the attractionbetween the molecules being directed away from the surfaces of anodeelectrode 60 and cathode electrode 62 as the surface molecules are moreattracted to the molecules within the water than they are to moleculesof the gas at the electrode surfaces. In contrast, molecules of the bulkof the water are equally attracted in all directions. Thus, in order toincrease the possible interaction energy, surface tension causes themolecules at the electrode surfaces to enter the bulk of the liquid.

In the embodiments in which gas-phase nanobubbles are generated, the gascontained in the nanobubbles (i.e., bubbles having diameters of lessthan about one micrometer) are also believed to be stable forsubstantial durations in the feed water, despite their small diameters.While not wishing to be bound by theory, it is believed that the surfacetension of the water, at the gas/liquid interface, drops when curvedsurfaces of the gas bubbles approach molecular dimensions. This reducesthe natural tendency of the nanobubbles to dissipate.

Furthermore, nanobubble gas/liquid interface is charged due to thevoltage potential applied across membrane 58. The charge introduces anopposing force to the surface tension, which also slows or prevents thedissipation of the nanobubbles. The presence of like charges at theinterface reduces the apparent surface tension, with charge repulsionacting in the opposite direction to surface minimization due to surfacetension. Any effect may be increased by the presence of additionalcharged materials that favor the gas/liquid interface.

The natural state of the gas/liquid interfaces appears to be negative.Other ions with low surface charge density and/or high polarizability(such as Cl⁻, ClO⁻, HO₂ ⁻, and O₂ ⁻) also favor the gas/liquidinterfaces, as do hydrated electrons. Aqueous radicals also prefer toreside at such interfaces. Thus, it is believed that the nanobubblespresent in the catholyte (i.e., the water flowing through cathodechamber 56) are negatively charged, but those in the anolyte (i.e., thewater flowing through anode chamber 54) will possess little charge (theexcess cations cancelling out the natural negative charge). Accordingly,catholyte nanobubbles are not likely to lose their charge on mixing withthe anolyte.

Additionally, gas molecules may become charged within the nanobubbles(such as O₂ ⁻), due to the excess potential on the cathode, therebyincreasing the overall charge of the nanobubbles. The surface tension atthe gas/liquid interface of charged nanobubbles can be reduced relativeto uncharged nanobubbles, and their sizes stabilized. This can bequalitatively appreciated as surface tension causes surfaces to beminimized, whereas charged surfaces tend to expand to minimizerepulsions between similar charges. Raised temperature at the electrodesurface, due to the excess power loss over that required for theelectrolysis, may also increase nanobubble formation by reducing localgas solubility.

As the repulsion force between like charges increases inversely as thesquare of their distances apart, there is an increasing outwardspressure as a bubble diameter decreases. The effect of the charges is toreduce the effect of the surface tension, and the surface tension tendsto reduce the surface whereas the surface charge tends to expand it.Thus, equilibrium is reached when these opposing forces are equal. Forexample, assuming the surface charge density on the inner surface of agas bubble (radius r) is Φ(e⁻/meter²), the outwards pressure(“P_(out)”), can be found by solving the NavierStokes equations to give:

P _(out)=Φ²/2Dε ₀   (Equation 1)

where D is the relative dielectric constant of the gas bubble (assumedunity), “ε₀” is the permittivity of a vacuum (i.e., 8.854 pF/meter). Theinwards pressure (“P_(in)”) due to the surface tension on the gas is:

P _(in)=2 g/r P _(out)   (Equation 2)

where “g” is the surface tension (0.07198 Joules/meter² at 25° C.).Therefore if these pressures are equal, the radius of the gas bubble is:

r=0.28792 ε₀/Φ².   (Equation 3)

Accordingly, for nanobubble diameters of 5 nanometers, 10 nanometers, 20nanometers, 50 nanometers, and 100 nanometers the calculated chargedensity for zero excess internal pressure is 0.20, 0.14, 0.10, 0.06 and0.04 e⁻/nanometer² bubble surface area, respectively. Such chargedensities are readily achievable with the use of an electrolysis cell(e.g., electrolysis cell 18). The nanobubble radius increases as thetotal charge on the bubble increases to the power ⅔. Under thesecircumstances at equilibrium, the effective surface tension of the fuelat the nanobubble surface is zero, and the presence of charged gas inthe bubble increases the size of the stable nanobubble. Furtherreduction in the bubble size would not be indicated as it would causethe reduction of the internal pressure to fall below atmosphericpressure.

In various situations within the electrolysis cell (e.g., electrolysiscell 18), the nanobubbles may divide into even smaller bubbles due tothe surface charges. For example, assuming that a bubble of radius “r”and total charge “q” divides into two bubbles of shared volume andcharge (radius r½=r/2^(1/3), and charge q_(1/2)=q/2), and ignoring theCoulomb interaction between the bubbles, calculation of the change inenergy due to surface tension (ΔE_(ST)) and surface charge (ΔE_(q))gives:

ΔE _(ST)=+2(4πγr _(1/2) ²)−4πγr ²=4πγr ²(2^(1/3)−1)   (Equation 3)

and

$\begin{matrix}{{\Delta \; E_{q}} = {{{{- 2}\left( {\frac{1}{2} \times \frac{\left( {q/2} \right)^{2}}{4\pi \; ɛ_{0}r_{1/2}}} \right)} - {\frac{1}{2} \times \frac{q^{2}}{4{\pi ɛ}_{0}r}}}\mspace{45mu} = {\frac{q^{2}}{8\pi \; ɛ_{0}r}\left( {1 - 2^{{- 2}/3}} \right)}}} & \left( {{Equation}\mspace{14mu} 4} \right)\end{matrix}$

The bubble is metastable if the overall energy change is negative whichoccurs when ΔE_(ST)+ΔE_(q) is negative, thereby providing:

$\begin{matrix}{{{\frac{q^{2}}{8\pi \; ɛ_{0}r}\left( {1 - 2^{{- 2}/3}} \right)} + {4\pi \; \gamma \; {r^{2}\left( {2^{1/3} - 1} \right)}}} \leq 0} & \left( {{Equation}\mspace{14mu} 5} \right)\end{matrix}$

which provides the relationship between the radius and the chargedensity (Φ):

$\begin{matrix}{\varphi = {\frac{q}{4\pi \; r^{2}} \geq \sqrt{\left( {\frac{2\gamma \; ɛ_{0}}{r}\frac{\left( {2^{1/3} - 1} \right)}{\left( {1 - 2^{{- 2}/3}} \right)}} \right)}}} & \left( {{Equation}\mspace{14mu} 6} \right)\end{matrix}$

Accordingly, for nanobubble diameters of 5 nanometers, 10 nanometers, 20nanometers, 50 nanometers, and 100 nanometers the calculated chargedensity for bubble splitting 0.12, 0.08, 0.06, 0.04 and 0.03e⁻/nanometer² bubble surface area, respectively. For the same surfacecharge density, the bubble diameter is typically about three timeslarger for reducing the apparent surface tension to zero than forsplitting the bubble in two. Thus, the nanobubbles will generally notdivide unless there is a further energy input.

The above-discussed gas-phase nanobubbles are adapted to attach to dirtparticles, thereby transferring their ionic charges. The nanobubblesstick to hydrophobic surfaces, which are typically found on typical dirtparticles, which releases water molecules from the high energywater/hydrophobic surface interface with a favorable negative freeenergy change. Additionally, the nanobubbles spread out and flatten oncontact with the hydrophobic surface, thereby reducing the curvatures ofthe nanobubbles with consequential lowering of the internal pressurecaused by the surface tension. This provides additional favorable freeenergy release. The charged and coated dirt particles are then moreeasily separated one from another due to repulsion between similarcharges, and the dirt particles enter the solution as colloidalparticles.

Furthermore, the presence of nanobubbles on the surface of particlesincreases the pickup of the particle by micron-sized gas-phase bubbles,which may also be generated during the electrochemical activationprocess. The presence of surface nanobubbles also reduces the size ofthe dirt particle that can be picked up by this action. Such pickupassist in the removal of the dirt particles from floor surfaces andprevents re-deposition. Moreover, due to the large gas/liquid surfacearea-to-volume ratios that are attained with gas-phase nanobubbles,water molecules located at this interface are held by fewer hydrogenbonds, as recognized by water's high surface tension. Due to thisreduction in hydrogen bonding to other water molecules, this interfacewater is more reactive than normal water and will hydrogen bond to othermolecules more rapidly, thereby showing faster hydration.

For example, at 100% efficiency a current of one ampere is sufficient toproduce 0.5/96,485.3 moles of hydrogen (H₂) per second, which equates to5.18 micromoles of hydrogen per second, which correspondingly equates to5.18×22.429 microliters of gas-phase hydrogen per second at atemperature of 0° C. and a pressure of one atmosphere. This also equatesto 125 microliters of gas-phase hydrogen per second at a temperature of20° C. and a pressure of one atmosphere. As the partial pressure ofhydrogen in the atmosphere is effectively zero, the equilibriumsolubility of hydrogen in the electrolyzed solution is also effectivelyzero and the hydrogen is held in gas cavities (e.g., macrobubbles,microbubbles, and/or nanobubbles).

Assuming the flow rate of the electrolyzed solution is 0.12 U.S. gallonsper minute, there is 7.571 milliliters of water flowing through theelectrolysis cell each second. Therefore, there are 0.125/7.571 litersof gas-phase hydrogen within the bubbles contained in each liter ofelectrolyzed solution at a temperature of 20° C. and a pressure of oneatmosphere. This equates to 0.0165 liters of gas-phase hydrogen perliter of solution less any of gas-phase hydrogen that escapes from theliquid surface and any that dissolves to supersaturate the solution.

The volume of a 10 nanometer-diameter nanobubble is 5.24×10⁻²² liters,which, on binding to a hydrophobic surface covers about 1.25×10⁻¹⁶square meters. Thus, in each liter of solution there would be a maximumof about 3×10⁻¹⁹ bubbles (at 20° C. and one atmosphere) with combinedsurface covering potential of about 4000 square meters. Assuming asurface layer just one molecule thick, this provides a concentration ofactive surface water molecules of over 50 millimoles. While thisconcentration represents a maximum amount, even if the nanobubbles havegreater volume and greater internal pressure, the potential for surfacecovering remains large. Furthermore, only a small percentage of the dirtparticles surfaces need to be covered by the nanobubbles for thenanobubbles to have a cleaning effect.

Accordingly, the gas-phase nanobubbles, generated during theelectrochemical activation process, are beneficial for attaching to dirtparticles so transferring their charge. The resulting charged and coateddirt particles are more readily separated one from another due to therepulsion between their similar charges. They will enter the solution toform a colloidal suspension. Furthermore, the charges at the gas/waterinterfaces oppose the surface tension, thereby reducing its effect andthe consequent contact angles. Also, the nanobubbles coating of the dirtparticles promotes the pickup of larger buoyant gas-phase macrobubblesand microbubbles that are introduced. In addition, the large surfacearea of the nanobubbles provides significant amounts of higher reactivewater, which is capable of the more rapid hydration of suitablemolecules.

4. Ion Exchange Membrane

As mentioned above, the ion exchange membrane 58 can include a cationexchange membrane (i.e., a proton exchange membrane) or an anionexchange membrane. Suitable cation exchange membranes for membrane 38include partially and fully fluorinated ionomers, polyaromatic ionomers,and combinations thereof. Examples of suitable commercially availableionomers for membrane 38 include sulfonated tetrafluorethylenecopolymers available under the trademark “NAFION” from E.I. du Pont deNemours and Company, Wilmington, Del.; perfluorinated carboxylic acidionomers available under the trademark “FLEMION” from Asahi Glass Co.,Ltd., Japan; perfluorinated sulfonic acid ionomers available under thetrademark “ACIPLEX” Aciplex from Asahi Chemical Industries Co. Ltd.,Japan; and combinations thereof. However, any ion exchange membrane canbe used in other examples.

5. Dispenser

The anolyte and catholyte EA liquid outputs can be coupled to adispenser 74, which can include any type of dispenser or dispensers,such as an outlet, fitting, spigot, spray head, a cleaning/sanitizingtool or head, etc. In the example shown in FIG. 1, dispenser 34 includesspray nozzle 14. There can be a dispenser for each output 70 and 72 or acombined dispenser for both outputs.

In one example, the anolyte and catholyte outputs are blended into acommon output stream 76, which is supplied to dispenser 74. As describedin Field et al. U.S. Patent Publication No. 2007/0186368, it has beenfound that the anolyte and catholyte can be blended together within thedistribution system of a cleaning apparatus and/or on the surface oritem being cleaned while at least temporarily retaining beneficialcleaning and/or sanitizing properties. Although the anolyte andcatholyte are blended, they are initially not in equilibrium andtherefore temporarily retain their enhanced cleaning and/or sanitizingproperties.

For example, in one embodiment, the catholyte EA water and the anolyteEA water maintain their distinct electrochemically activated propertiesfor at least 30 seconds, for example, even though the two liquids areblended together. During this time, the distinct electrochemicallyactivated properties of the two types of liquids do not neutralizeimmediately. This allows the advantageous properties of each liquid tobe utilized during a common cleaning operation. After a relatively shortperiod of time, the blended anolyte and catholyte EA liquid on thesurface being cleaned quickly neutralize substantially to the originalpH and ORP of the source liquid (e.g., those of normal tap water). Inone example, the blended anolyte and catholyte EA liquid neutralizesubstantially to a pH between pH6 and pH8 and an ORP between ±50 mVwithin a time window of less than 1 minute from the time the anolyte andcatholyte EA outputs are produced by the electrolysis cell. Thereafter,the recovered liquid can be disposed in any suitable manner.

However, in other embodiments, the blended anolyte and catholyte EAliquid can maintain pHs outside of the range between pH6 and pH8 andORPs outside the range of ±50 mV for a time greater than 30 seconds,and/or can neutralize after a time range that is outside of 1 minute,depending on the properties of the liquid.

6. Electrolysis Cell With No Ion-Selective Membrane

FIG. 3 illustrates an electrolysis cell 80 having no ion-selectivemembrane according to a further example of the disclosure. Cell 80includes a reaction chamber 82, an anode 84 and a cathode 86. Chamber 82can be defined by the walls of cell 80, by the walls of a container orconduit in which electrodes 84 and 86 are placed, or by the electrodesthemselves, for example. Anode 84 and cathode 86 may be made from anysuitable material or a combination of materials, such as a conductivepolymer, titanium and/or titanium coated with a precious metal, such asplatinum. Anode 84 and cathode 86 are connected to a conventionalelectrical power supply, such as batteries 32 shown in FIG. 1. In oneembodiment, electrolytic cell 80 includes its own container that defineschamber 82 and is located in the flow path of the liquid to be treated,such as within the flow path of a hand-held spray bottle or mobile floorcleaning apparatus.

During operation, liquid is supplied by a source 88 and introduced intoreaction chamber 82 of electrolysis cell 80. In the embodiment shown inFIG. 3, electrolysis cell 80 does not include an ion exchange membranethat separates reaction products at anode 84 from reaction products atcathode 86. In the example in which tap water is used as the liquid tobe treated for use in cleaning, after introducing the water into chamber82 and applying a voltage potential between anode 84 and cathode 86,water molecules in contact with or near anode 84 are electrochemicallyoxidized to oxygen (O₂) and hydrogen ions (H⁺) while water molecules incontact or near cathode 86 are electrochemically reduced to hydrogen gas(H₂) and hydroxyl ions (OH⁻). Other reactions can also occur and theparticular reactions depend on the components of the liquid. Thereaction products from both electrodes are able to mix and form anoxygenated fluid 89 (for example) since there is no physical barrier,for example, separating the reaction products from each other.Alternatively, for example, anode 84 can be separated from cathode 84 byusing a dielectric barrier such as a non-permeable membrane (not shown)disposed between the anode and cathode.

7. Electrode Pattern Examples

As mentioned above, at least one of the anode or cathode electrodes canbe formed at least partially or wholly of a conductive polymer, such asthose used for static dissipating devices. Examples of suitableconductive polymers are commercially available from RTP Company ofWinona, Minn., USA. For example, the electrodes can be formed of aconductive plastic compound having a surface resistivity of 10⁰ to 10¹²ohm/sq, such as 10¹ to 10⁶ ohm/sq. However, electrodes having surfaceresistivities outside those ranges can be used in other examples.

With conductive polymer, the electrodes can be easily molded orotherwise formed in any desired shape. For example, the electrodes canbe injection molded. As mentioned above, one or more of the electrodescan form a mesh, with regular-sized rectangular openings in the form ofa grid. However, the openings or apertures can have any shape, such ascircular, triangular, curvilinear, rectilinear, regular and/orirregular. Curvilinear apertures have at least one curved edge. Wheninjection molded, for example, the shapes and sizes of the apertures canbe easily tailored to a particular pattern. However, these patterns canalso be formed in metallic electrodes in other examples of the presentdisclosure.

The apertures can be sized and positioned to increase the surface areaof the electrode for electrolysis and thereby promote generation of gasbubbles in the liquid being treated.

FIG. 4A is a fragmentary view of a conductive polymer electrode 100having a plurality of rectilinear (e.g., rectangular) apertures 102 in aregular grid pattern according to an aspect of the disclosure.

FIG. 4B is a fragmentary view of a conductive polymer electrode 104having a plurality of curvilinear (e.g., circular) apertures 106 ofdifferent sizes in a regular grid pattern according to another example.The use of differently sized apertures in the same electrode may promotegeneration of differently sized gas bubbles along the edges of theapertures during electrolysis.

FIG. 4C is a fragmentary view of a conductive polymer electrode 108having a plurality of irregular and regular shaped apertures 110 havinga variety of different shapes and sizes according to another example. Inthis example, various apertures 110 define various opening areas. One ormore of the apertures 110 can include one or more internal points, suchas points 112, that are believed to promote further gas bubble andreactive species generation during electrolysis. These apertures formpolygons having at least one internal angle (e.g., at point 112) that isgreater than 180 degrees. In an alternative embodiment, the apertureshave a plurality of internal angles greater than 180 degrees.

In addition, the electrodes can be formed with one or more othernon-uniform features, such as spikes or burs that further increase theelectrode surface area. The spikes can be arranged in a regular patternor an irregular pattern and can have the same sizes and shapes or canhave different sizes and/or shapes.

For example, an electrolysis cell can be constructed to include an anodeand a cathode, wherein at least one of the anode electrode or thecathode electrode comprises a first plurality of apertures having afirst size (and/or shape) and a second plurality of apertures having asecond, different size (and/or shape). In one example, the electrolysiscell also includes an ion selective membrane disposed between the anodeelectrode and the cathode electrode and which defines a respective anodechamber and cathode chamber.

In a further example, at least two apertures of a set comprising thefirst and second plurality of apertures have different shapes (and/orsizes) than one another. In a further example, at least three aperturesof a set comprising the first and second plurality of apertures havedifferent shapes (and/or sizes) than one another.

The first and second plurality of apertures can have polygon shapesand/or curvilinear shapes formed of at least one curved edge. At leastone of the first plurality or the second plurality of apertures can bearranged in a regular pattern or in an irregular pattern.

At least one aperture of the first plurality or the second plurality ofapertures can have a polygon shape with at least one internal angle thatis greater than 180 degrees.

In a further example, the electrodes shown in FIGS. 4A-4C are fabricatedof a conductive metallic material. For example as shown in FIG. 4A, theelectrode 100 can be formed of a metallic mesh, which can be plated withanother material such as platinum or can be unplated.

8. Tubular Electrode Example

The electrodes themselves can have any suitable shape, such as planar,coaxial plates, cylindrical rods, or a combination thereof. FIG. 5illustrates an example of an electrolysis cell 200 having a tubularshape according to one illustrative example. Portions of cell 200 arecut away for illustration purposes. In this example, cell 200 is anelectrolysis cell having a tubular housing 202, a tubular outerelectrode 204, and a tubular inner electrode 206, which is separatedfrom the outer electrode by a suitable gap, such as 0.040 inches. Othergap sizes can also be used, such as but not limited to gaps in the rangeof 0.020 inches to 0.080 inches. Either of the inner or outer electrodecan serve as the anode/cathode, depending upon the relative polaritiesof the applied voltages.

In one example, outer electrode 204 and inner electrode 206 haveconductive polymer constructions with apertures such as those shown inFIGS. 4A-4C, for example. However, one or both electrodes can have asolid construction in another example.

The electrodes 206 and 206 can be made from any suitable material, suchas a conductive polymer, titanium and/or titanium coated with a preciousmetal, such as platinum, or any other suitable electrode material. Inaddition, multiple cells 200 can be coupled in series or in parallelwith one another, for example.

In a specific example, at least one of the anode or cathode electrodesis formed of a metallic mesh, with regular-sized rectangular openings inthe form of a grid. In one specific example, the mesh is formed of0.023-inch diameter T316 stainless steel having a grid pattern of 20×20grid openings per square inch. However, other dimensions, arrangementsand materials can be used in other examples.

An ion-selective membrane 208 is positioned between the outer and innerelectrodes 204 and 206. In one specific example, the ion-selectivemembrane includes a “NAFION” from E.I. du Pont de Nemours and Company,which has been cut to 2.55 inches by 2.55 inches and then wrapped aroundinner tubular electrode 206 and secured at the seam overlap with acontact adhesive, for example, such as a #1357 adhesive from 3M Company.Again, other dimensions and materials can be used in other examples.

In this example, the volume of space within the interior of tubularelectrode 206 is blocked by a solid inner core 209 to promote liquidflow along and between electrodes 204 and 206 and ion-selective membrane208. This liquid flow is conductive and completes an electrical circuitbetween the two electrodes. Electrolysis cell 200 can have any suitabledimensions. In one example, cell 200 can have a length of about 4 incheslong and an outer diameter of about ¾ inch. The length and diameter canbe selected to control the treatment time and the quantity of bubbles,e.g., nanobubbles and/or microbubbles, generated per unit volume of theliquid.

Cell 200 can include a suitable fitting at one or both ends of the cell.Any method of attachment can be used, such as through plasticquick-connect fittings. For example, one fitting can be configured toconnect to the output tube 20 shown in FIG. 1. Another fitting can beconfigured to connect to the inlet filter 16 or an inlet tube, forexample. In another example, one end of cell 200 is left open to drawliquid directly from reservoir 12 in FIG. 1.

In the example shown in FIG. 5, cell 200 produces anolyte EA liquid inthe anode chamber (between one of the electrodes 204 or 206 andion-selective membrane 208) and catholyte EA liquid in the cathodechamber (between the other of the electrodes 204 or 206 andion-selective membrane 208). The anolyte and catholyte EA liquid flowpaths join at the outlet of cell 200 as the anolyte and catholyte EAliquids enter tube 20 (in the example shown in FIG. 1). As a result,spray bottle 10 dispenses a blended anolyte and catholyte EA liquidthrough nozzle 14.

In one example, the diameters of tubes 20 and 22 are kept small so thatonce pump 24 and electrolysis cell 18 (e.g., cell 200 shown in FIG. 5)are energized, tubes 20 and 22 are quickly primed withelectrochemically-activated liquid. Any non-activated liquid containedin the tubes and pump are kept to a small volume. Thus, in theembodiment in which the control electronics 30 activate pump andelectrolysis cell in response to actuation of switch 28, spray bottle 10produces the blended EA liquid at nozzle 14 in an “on demand” fashionand dispenses substantially all of the combined anolyte and catholyte EAliquid (except that retained in tubes 20, 22 and pump 24) from thebottle without an intermediate step of storing the anolyte and catholyteEA liquids. When switch 28 is not actuated, pump 24 is in an “off” stateand electrolysis cell 18 is de-energized. When switch 28 is actuated toa closed state, control electronics 30 switches pump 24 to an “on” stateand energizes electrolysis cell 18. In the “on” state, pump 24 pumpswater from reservoir 12 through cell 18 and out nozzle 14.

Other activation sequences can also be used. For example, controlcircuit 30 can be configured to energize electrolysis cell 18 for aperiod of time before energizing pump 24 in order to allow the feedwater to become more electrochemically activated before dispensing.

The travel time from cell 18 to nozzle 14 can be made very short. In oneexample, spray bottle 10 dispenses the blended anolyte and catholyteliquid within a very small period of time from which the anolyte andcatholyte liquids are produced by electrolysis cell 18. For example, theblended liquid can be dispensed within time periods such as within 5seconds, within 3 seconds, and within 1 second of the time at which theanolyte and catholyte liquids are produced.

9. Control Circuit

Referring back to FIG. 1, control electronics 30 can include anysuitable control circuit, which can be implemented in hardware,software, or a combination of both, for example.

Control circuit 30 includes a printed circuit board containingelectronic devices for powering and controlling the operation of pump 24and electrolysis cell 18. In one example, control circuit 30 includes apower supply having an output that is coupled to pump 24 andelectrolysis cell 18 and which controls the power delivered to the twodevices. Control circuit 30 also includes an H-bridge, for example, thatis capable of selectively reversing the polarity of the voltage appliedto electrolysis cell 18 as a function of a control signal generated bythe control circuit. For example, control circuit 30 can be configuredto alternate polarity in a predetermined pattern, such as every 5seconds with a 50% duty cycle. In another example, described in moredetail below, control circuit 30 is configured to apply a voltage to thecell with primarily a first polarity and periodically reverse thepolarity for only very brief periods of time. Frequent reversals ofpolarity can provide a self-cleaning function to the electrodes, whichcan reduce scaling or build-up of deposits on the electrode surfaces andcan extend the life of the electrodes.

In the context of a hand-held spray bottle, it is inconvenient to carrylarge batteries. Therefore, the available power to the pump and cell issomewhat limited. In one example, the driving voltage for the cell is inthe range of about 8 Volts to about 28 Volts. But since typical flowrates through the spray bottle and electrolysis cell are fairly low,only relatively small currents are necessary to effectively activate theliquid passing through the cell. With low flow rates, the residence timewithin the cell is relatively large. The longer the liquid resides inthe cell while the cell is energized, the greater the electrochemicalactivation (within practical limits). This allows the spray bottle toemploy smaller capacity batteries and a DC-to-DC converter, which stepsthe voltage up to the desired output voltage at a low current.

For example, the spray bottle can carry one or more batteries having anoutput voltage of about 3-9 Volts. In one particular example, the spraybottle can carry four AA batteries, each having a nominal output voltageof 1.5 Volts at about 500 milliampere-hours to about 3 ampere-hours. Ifthe batteries are connected in series, then the nominal output voltagewould be about 6V with a capacity of about 500 milliampere-hours toabout 3 ampere-hours. This voltage can be stepped up to the range of 18Volts to 28 Volts, for example, through the DC-to-DC converter. Thus,the desired electrode voltage can be achieved at a sufficient current.

In another particular example, the spray bottle carries 10 nickel-metalhydride batteries, each having a nominal output voltage of about 1.2Volts. The batteries are connected in series, so the nominal outputvoltage is about 10V to 12.5V with a capacity of about 1800milliampere-hours. This voltage is stepped up/down to a range of 8 Voltsto at least 28 Volts, for example, through the DC-to-DC converter. Thus,the desired electrode voltage can be achieved at a sufficient current.

The ability to produce a large voltage and a suitable current throughthe cell can be beneficial for applications in which regular tap wateris fed through the cell to be converted into a liquid having enhancedcleaning and/or sanitizing properties. Regular tap water has arelatively low electrical conductivity between the electrodes of thecell.

Examples of suitable DC-to-DC converters include the Series A/SM surfacemount converter from PICO Electronics, Inc. of Pelham, N.Y., U.S.A. andthe NCP3064 1.5A Step-Up/Down/Inverting Switching regulator from ONSemiconductor of Phoenix, Ariz., U.S.A, connected in a boostapplication.

In one example, the control circuit controls the DC-to-DC converterbased on a sensed current drawn from the electrolysis cell so that theDC-to-DC converter outputs a voltage that is controlled to achieve acurrent draw through the cell that is within a predetermined currentrange. For example, the target current draw is about 400 milliamperes inone specific example. In another example, the target current is 350milliamperes. Other currents and ranges can be used in alternativeembodiments. The desired current draw may depend on the geometry of theelectrolysis cell, the properties of the liquid being treated and thedesired properties of the resulting electrochemical reaction.

Block diagrams illustrating examples of the control electronics aredescribed in more detail below with respect to FIGS. 7 and 20.

10. Driving Voltage for Electrolysis Cell

As described above, the electrodes of the electrolysis cell can bedriven with a variety of different voltage and current patterns,depending on the particular application of the cell. It is desirable tolimit scaling on the electrodes by periodically reversing the voltagepolarity that is applied to the electrodes. Therefore, the terms “anode”and “cathode” and the terms “anolyte” and “catholyte” as used in thedescription and claims are respectively interchangeable. This tends torepel oppositely-charged scaling deposits.

In one example, the electrodes are driven at one polarity for aspecified period of time (e.g., about 5 seconds) and then driven at thereverse polarity for approximately the same period of time. Since theanolyte and catholyte EA liquids are blended at the outlet of the cell,this process produces essentially one part anolyte EA liquid to one partcatholyte EA liquid.

In another example, the electrolysis cell is controlled to produce asubstantially constant anolyte EA liquid or catholyte EA liquid fromeach chamber without complicated valving. In prior art electrolysissystems, complicated and expensive valving is used to maintain constantanolyte and catholyte through respective outlets while still allowingthe polarity to be reversed to minimize scaling. For example, looking atFIG. 2, when the polarity of the voltage applied to the electrodes isreversed, the anode 60 becomes a cathode, and the cathode 62 becomes ananode. Outlet 70 will deliver catholyte instead of anolyte, and outlet72 will deliver anolyte instead of catholyte. Therefore, with the priorart approach, valving could be used to connect outlet 70 to cathodechamber 56 and outlet 72 to anode chamber 54 when the voltage isreversed. This results in a constant anolyte or catholyte flow througheach output. Instead of using this complicated valving, one example ofthe present disclosure achieves substantially constant outputs throughthe voltage pattern supplied to the electrodes.

FIG. 6 is a waveform diagram illustrating the voltage pattern applied tothe anode and cathode according to an exemplary aspect of the presentdisclosure. A substantially constant, relatively positive voltage isapplied to the anode, while a substantially constant, relativelynegative voltage is applied to the cathode. However, periodically eachvoltage is briefly pulsed to a relatively opposite polarity to repelscale deposits. In this example, a relatively positive voltage isapplied to the anode and a relatively negative voltage is applied to thecathode from times t0-t1, t2-t3, t4-t5 and t6-t7. During times t1-t2,t3-t4, t5-t6 and t7-t8, the voltages applied to each electrode isreversed. The reversed voltage level can have the same magnitude as thenon-reversed voltage level or can have a different magnitude if desired.

The frequency of each brief polarity switch can be selected as desired.As the frequency of reversal increases, the amount of scaling decreases.However, the electrodes may loose small amounts of platinum (in the caseof platinum coated electrodes) with each reversal. As the frequency ofreversals decreases, scaling may increase. In one example, the timeperiod between reversals, as shown by arrow 300, is in the range ofabout 1 second to about 600 seconds. Other periods outside this rangecan also be used.

The time period at which the voltages are reversed can also be selectedas desired. In one example, the reversal time period, represented byarrow 302, is in the range of about 50 milliseconds to about 100milliseconds. Other periods outside this range can also be used. In thisexample, time period of normal polarity 303, such as between times t2and t3, is at least 900 milliseconds.

Also, the voltage can be selectively reversed periodically ornon-periodically. In one particular example, the time period 300 betweenreversals is 1 second, and during each period of the waveform, thevoltage between the electrodes is applied with the normal polarity for900 milliseconds and then with the reversed polarity for 100milliseconds.

With these ranges, for example, each anode chamber produces asubstantially constant anolyte EA liquid output, and each cathodechamber produces a substantially constant catholyte EA output withoutrequiring valving.

If the number of anode electrodes is different than the number ofcathode electrodes, e.g., a ratio of 3:2, or if the surface area of theanode electrode is different than the surface area of the cathodeelectrode, then the applied voltage pattern can be used in theabove-manner to produce a greater amount of either anolyte or catholyteto emphasize cleaning or sanitizing properties of the produced liquid.For example, if cleaning is to be emphasized, then a greater number ofelectrodes can be driven to the relatively negative polarity (to producemore catholyte) and a lesser number of electrodes can be driven to therelatively positive polarity (to produce less anolyte). If sanitizing isto be emphasized, then a greater number of electrodes can be driven tothe relatively positive polarity (to produce more anolyte) and a lessernumber of electrodes can be driven to the relatively negative polarity(to produce less catholyte).

If the anolyte and catholyte outputs are blended into a single outputstream prior to dispensing, then the combined anolyte and catholyteoutput liquid can be tailored to emphasize cleaning over sanitizing orto emphasize sanitizing over cleaning. In one embodiment, the controlcircuit includes a further switch, which allows the user to selectbetween cleaning and sanitizing modes. For example, in the embodimentshown in FIG. 1, spray bottle 10 can include a user-operablecleaning/sanitizing mode switch that is mounted to the bottle.

In one exemplary embodiment of the disclosure, a hand-held spray bottlesuch as those shown in FIGS. 1 and 8 carries tubular electrolysis cellsuch as cell 200 shown in FIG. 5. The electrolysis cell is driven with avoltage to emphasize enhanced cleaning properties by generating agreater amount of catholyte EA liquid than anolyte EA liquid per unit oftime. In cell 200, outer cylindrical electrode 204 has a greaterdiameter and therefore a greater surface area than inner cylindricalelectrode 206. To emphasize enhanced cleaning properties, the controlcircuit drives cell 200 so that, for the majority of period of thedriving voltage pattern, outer electrode 204 serves as the cathode andinner electrode 206 serves as the anode. Since the cathode has a largersurface area than the anode, cell 200 will generate more catholyte thananolyte per unit of time through the combined outlet of the cell.Referring to FIG. 6, in this example, the control circuit applies arelatively positive voltage to the anode (electrode 206) and arelatively negative voltage to the cathode (electrode 204) from timest0-t1, t2-t3, t4-t5 and t6-t7. During times t1-t2, t3-t4, t5-t6 andt7-t8, applied to each electrode is briefly reversed.

In this example, the spray bottle is filled with regular tap water only.Thus the liquid that is pumped through and electrochemically activatedwith cell 200 consists solely of regular tap water. The tap water iselectrochemically activated, as discussed herein, and dispensed as ablended anolyte and catholyte stream through the spray nozzle. The sprayoutput therefore has enhanced cleaning properties, wherein the amount ofcatholyte exceeds the amount of anolyte in the blended stream. Enhancedsanitizing properties can be emphasized in an alternative embodiment bymaking electrode 204 primarily an anode and electrode 206 primarily acathode using the waveforms shown in FIG. 6, for example.

It has been found that such frequent, brief polarity reversals forde-scaling the electrodes may have a tendency also to shed materialsoften used for plating the electrodes, such as platinum, from theelectrode surface. Thus in one embodiment, electrodes 204 and 206comprise unplated electrodes, such as metallic electrodes or conductiveplastic electrodes. For example, the electrodes can be unplated metallicmesh electrodes.

11. Status Indicator Light Illuminating Through Liquid 11.1 ControlCircuit for Bottles Shown in FIGS. 1 and 8-16

Another aspect of the present disclosure relates to providing ahumanly-perceptible indicator, which indicates a functional status ofthe electrolysis cell, such as the oxidation-reduction potential of theEA liquid. The spray bottle and/or other devices disclosed herein can bemodified to include a visual indicator of the output liquid'soxidation-reduction potential.

The level of power consumed by the electrolysis cell can be used todetermine whether the cell is operating correctly and therefore whetherthe liquid (sparged water, EA anolyte, and/or EA catholyte) produced bythe cell is electrochemically activated to a sufficient level. Powerconsumption below a reasonable level can reflect various potentialproblems such as use of ultra-pure feed water or feed water having agenerally low electrolyte content (e.g., low sodium/mineral content)such that the water does not conduct a sufficient level of electricalcurrent within the functional generator. The current consumption cantherefore also indicate high or low levels of oxidation-reductionpotential, for example. Also, the current drawn by the pump may be usedto indicate whether the pump is operating correctly or whether there isa problem, such as the pump being stalled.

FIG. 7 is a block diagram of a system 400 having an indicator accordingto an embodiment of the disclosure, which can be incorporated into anyof the embodiments disclosed herein, for example. System 400 includespower supply (such as a battery) 402, control electronics 404,electrolysis cell 406, pump 408, current sensors 410 and 412, indicatorlights 414 and 416, switch 418 and trigger 420. For simplicity, theliquid inputs and outputs of electrolysis cell 404 are not shown in FIG.7. All elements of system 400 can be powered by the same power supply402 or by two or more separate power supplies, for example.

Control electronics 404 are coupled to control the operating state ofelectrolysis cell 406, pump 408 and indicator lights 414 and 416 basedon the present operating mode of system 400 and user control inputs,such as trigger 420. In this example, switch 418 is coupled in seriesbetween power supply 402 and control electronics 404 and serves tocouple and decouple power supply 402 to and from power inputs of controlelectronics 404 depending on the state of trigger 420. In oneembodiment, switch 418 includes a momentary, normally-open switch thatcloses when trigger 420 is depressed and opens when trigger 420 isreleased.

In an alternative example, switch 418 is configured as an on/off toggleswitch, for example, that is actuated separately from trigger 420.Trigger 420 actuates a second switch that is coupled to an enable inputof control electronics 404. Other configurations can also be used.

In both embodiments, when trigger 420 is depressed, control electronics404 is enabled and generates appropriate voltage outputs for drivingelectrolysis cell 406 and pump 408. For example, control electronics 404can produce a first voltage pattern for driving the electrolysis cell406, such as those patterns described herein, and a second voltagepattern for driving pump 408. When trigger 420 is released, controlelectronics is powered off and/or otherwise disabled from producing theoutput voltages to cell 406 and pump 408.

Current sensors 410 and 412 are coupled in electrical series withelectrolysis cell 406 and pump 408, respectively, and each provide asignal to control electronics 404 that is representative of therespective electrical current drawn through cell 406 or pump 406. Forexample, these signals can be analog or digital signals.

In one particular example, system 400 includes a sensor 410 for sensingthe current drawn by electrolysis cell 406, but no sensor 412 forsensing current drawn by pump 408. The control electronics 404 includesa microcontroller, such as an MC9S08SH4CTG-ND Microcontroller availablefrom Digi-Key Corporation of Thief River Falls, Minn., U.S.A., whichcontrols a DRV8800 full bridge motor driver circuit available from TexasInstruments Corporation of Dallas, Tex., U.S.A. The driver circuit hasan H-switch that drives the output voltage to electrolysis cell 406according to a voltage pattern controlled by the microcontroller. TheH-switch has a current sense output that can be used by themicrocontroller to sense the current drawn by cell 406.

Control electronics 404 compares the sensor outputs to predeterminedthreshold current levels or ranges and then operates indicators 414 and416 as a function of one or both of the comparisons. The thresholdcurrent levels or ranges can be selected to represent predeterminedpower consumption levels, for example.

Indicators 414 and 416 each can include any visually perceptibleindicator, such as an LED. In one example, indicator lights 414 and 416have different colors to indicate different operating states. Forexample, indicator light 414 might be green, which when illuminatedindicates a normal, properly functioning electrolysis cell and/or pump,and indicator 416 might be red, which when illuminated indicates aproblem in the operating state of the electrolysis cell and/or pump. Ina particular example, the bottle contains four green LEDs 414 and fourred LEDs 416 for a strong illumination of the liquid contained in thebottle.

In the example shown in FIG. 7, control electronics 404 operate theindicator lights 414 and 416 as a function of the current levels sensedby current sensors 410 and/or 412. For example, control electronics 404can turn off (or alternatively, turn on) one or both of the indicatorlights as a function of whether the current level sensed is above orbelow a threshold level or within a range. Indicator lights 414 and 416can be operated by separate power signals and a common ground, forexample, provided by control electronics 404.

In one embodiment, control electronics 404 illuminates the greenindicator light 414 in a steady “on” state and turns off the redindicator light 416 when the sensed current level the cell 406 is abovethe respective threshold level (or within the predefined range). Incontrast, control electronics 404 illuminates the red indicator light416 in a steady “on” state and the green indicator light 414 in a steady“off” state when the sensed current level of cell 406 is below therespective threshold level.

The control electronics 404 modulates the green indicator light 414between the on and off states when the current drawn by pump 408 isoutside of a predetermined range. Any suitable range can be used for thepump current, such as between 1.5 Amps and 0.1 Amps. Other ranges canalso be used. In a further example, control electronics 404 illuminatesthe green indicator light 414 in a steady “on” state and turns off thered indicator light 416 when the sensed current levels of both the cell406 and the pump 408 are within their respective predetermined, and ifnot, illuminates the red indicator light 416 and turns off the greenindicator light 414.

In another embodiment, one or more indicator lights are operated in asteady “on” state when the sensed current level is above the thresholdlevel, and are cycled between the “on” state and “off” state at aselected frequency to indicate a problem when the sensed current levelof electrolysis cell 406 is below the threshold level. Multiplethreshold levels and frequencies can be used in other embodiments. Also,a plurality of separately-controlled indicator lights can be used, eachindicating operation within a predefined range. Alternatively or inaddition, the control electronics can be configured to alter theillumination level of one or more indicator lights as a function of thesensed current level relative to one or more thresholds or ranges, forexample. In a further example, separate indicator lights can be used forseparately indicating the operating state of the electrolysis cell andthe pump. Other configurations can also be used.

11.2 Illumination Through the Liquid

As described in more detail below, indicator lights 414 and/or 416 canbe positioned on the apparatus (such as on the spray bottle) toilluminate the liquid itself, either prior to treatment by electrolysiscell 404 and/or after treatment. For example, the indicator light, whenilluminated, generates luminous flux in the visible wavelength rangethat is visually perceptible through the liquid from a viewpoint that isexterior to the apparatus. For example, the liquid may diffuse at leasta portion of the light, giving a visual impression that the liquid,itself, is illuminated. In one embodiment, the apparatus comprises acontainer, lumen or other element that contains the liquid and comprisesa material and/or portion that is at least translucent and positioned totransmit at least some of the light produced by indicator 414 and/or 416when illuminated. This container, lumen or other element is at leastpartially visible from an exterior of the apparatus.

The term “at least translucent” includes translucent, semi-transparent,fully transparent, and any term that means at least some of the lightilluminating from the indicator is humanly perceptible through thematerial.

FIGS. 8-16 illustrate examples of a hand-held spray bottle 500 and 500′having an electrolysis cell and at least one indicator light, wherein atleast some of the light illuminating from the indicator is humanlyperceptible from a viewpoint that is external to the bottle. Theparticular bottle configurations and constructions shown in the drawingsare provided as non-limiting examples only. The same reference numeralsare used in FIGS. 8-16 for the same or similar elements.

Referring to FIG. 8A, bottle 500 includes a housing 501 forming a base502, a neck 504, and a barrel or head 506. The tip of barrel 506includes a nozzle 508 and a drip/splash guard 509. Drip/splash guard 509also serves as a convenient hook for hanging bottle 500 on a utilitycart, for example. As shown in more detail below, housing 501 has aclamshell-type construction with substantially symmetrical left andright hand sides attached together, such as by screws. Base 502 houses acontainer 510, which serves as a reservoir for liquid to be treated andthen dispensed through nozzle 508. Container 510 has a neck and threadedinlet (with a screw cap) 512 that extends through base 502 to allowcontainer 510 to be filled with a liquid. Inlet 512 is threaded toreceive a cap seal.

In this example, the side walls of housing base 502 have a plurality ofopenings or windows 520 about its circumference through which container510 is visible. In this example, the openings 520 are formed by anabsence of the housing material within the opening. In another example,the openings are formed by a material that is at least translucent. Inanother example, shown in FIG. 8B, the entire housing or a portion ofthe housing is at least translucent.

Similarly, container 510 is formed of a material that is at leasttranslucent. For example, container 510 can be fabricated as a blow moldof a clear polyester material. As explained in more detail below,housing 501 also contains a circuit board carrying a plurality of LEDindicator lights 594, 596 (corresponding to lights 414 and 416 shown inFIG. 7). The lights are positioned beneath the base of container 510 totransmit light through a base wall of container 510 and into any liquidcontained in the container. The liquid diffuses at least a portion ofthe light, giving an appearance of the liquid being illuminated. Thisillumination is visible from a viewpoint external to housing 501,through openings 520. The color of the light and/or other illuminationcharacteristics such as on/off modulation, intensity, etc. that arecontrolled by the control electronics are observable through openings510 to give the user an indication of the functional status of thebottle. Arrows 522 represent illumination from the indicator light thatis transmitted through the liquid in container 510 and visible from anexterior of the bottle, through openings 520 in housing 501.

For example, the liquid can be illuminated with a green LED to indicatethat the electrolysis cell and/or pump are functioning properly. Thus,the user can be assured that the treated liquid dispensed from nozzle508 has enhanced cleaning and/or sanitizing properties as compared tothe source liquid contained in container 510. Also, illumination of thesource liquid in container 510, although not yet treated, gives animpression that the liquid is “special” and has enhanced properties.

Similarly, if the electrolysis cell and/or pump are not functioningproperly, the control electronics illuminates the red LED, giving thesource liquid a red appearance. This gives the user an impression thatthere is a problem and that the dispensed liquid may not have enhancedcleaning and/or sanitizing properties.

Although in the example shown in FIG. 8A the illumination is visiblethrough container 510, the indicator lights can be positioned toilluminate any portion of the flow path from a liquid inlet to thebottle and nozzle 508, including any elements upstream and/or downstreamof the electrolysis cell. The housing can be modified in any manner toallow this illumination to be visible by a user. For example, the liquidcan be illuminated in a delivery tube extending from the output of theelectrolysis cell to the nozzle 508. Barrel 506 can be modified toinclude an opening to expose the delivery tube, or a portion of the tubecan extend along the exterior of barrel 506, for example.

FIG. 8B is a perspective view of a bottle 500′ which lacks the windows520 if the embodiment shown in FIG. 8A. In this example, the entirehousing 501 or a portion of the housing is at least translucent. Forexample, housing 501 can be fabricated of polycarbonate. The samereference numerals are used in FIG. 8B as were used in FIG. 8A for thesame or similar elements. Although not expressly shown in FIG. 8B, witha translucent housing, the internal components of bottle 500′ arevisible through housing 501 from a viewpoint that is external to thehousing. For example, the container 510 (shown in phantom) and theliquid contained therein are visible through housing 501. In thisexample, there are four red LEDs 594 and four green LEDs 596 (also shownin phantom), arranged in pairs in each corner of the bottle. Thus, whenLEDs 594 and/or 596 are illuminated, the liquid diffuses at least aportion of the light, giving an appearance of the liquid beingilluminated. This illumination is visible from a viewpoint external tohousing 501 in the same manner as shown in FIG. 8A, except illuminationwould not be limited to the “windows” 520.

FIG. 8C is a perspective view of the back end of the barrel (or head)506 of bottle 501′, which illustrates an electrical power jack 523 forconnecting to the cord of a battery charger (not shown). In the examplein which bottle 500′ carries rechargeable batteries, these batteries canbe recharged through jack 523.

FIGS. 9-16 illustrate further details of the particular bottle 500′shown in FIG. 8B.

FIGS. 9A and 9B are perspective views of the left-hand side 501A ofhousing 501, and FIG. 9C is a perspective view of the right-hand side501B of housing 501.

The left and right hand sides 501A and 501B, when attached to oneanother form a plurality of compartments for containing various elementsof the bottle. For example, housing base 502 includes a firstcompartment 531 for containing liquid container 510 (shown in FIGS. 8A,8B), a second compartment 532 for containing a circuit board supportingthe control electronics, and a third compartment 533 for containing aplurality of batteries to power the control electronics. Barrel 506includes a compartment 534 for containing the electrolysis cell andpump.

FIG. 10 illustrates various components installed in the left-hand side501A of housing 501. Container 510 is installed in compartment 531,circuit board 540 is installed in compartment 532, batteries 542 areinstalled in compartment 533, and pump/cell assembly 544 is installed incompartment 534. The various tubes that connect container 510, pump/cellassembly and nozzle 508 are not shown in FIG. 10.

FIGS. 11A and 11B illustrate container 510 in greater detail. FIG. 11Ais a perspective view of container 510, and FIG. 11B is a fragmentary,cross-sectional view of the inlet 512 of container 510 installed inhousing 501A. An o-ring 548 seals the outer diameter surface of the neckof inlet 512 within housing 501A. The threads on inlet 512 receive a cap(not shown) to seal the inlet opening. Container 510 further includes anoutlet 549 for receiving a tube (not shown) for drawing liquid fromcontainer 510. The tube may include an inlet filter as described withreference to FIG. 1, for example.

FIG. 12A illustrates a fragmentary, close-up view of pump/cell assembly544 installed in the barrel 506 of housing half 501A. FIG. 12B is aperspective view of pump/cell assembly 544 removed from the housing.FIG. 12C shows a bottom, perspective view of the assembly with thetrigger 570 removed.

Pump/cell assembly 544 includes a pump 550 and an electrolysis cell 552mounted within a bracket 554. The pump 550 has a first port 555 that isfluidically coupled to the tube (not shown) extending from the outlet549 of container 510 and a second port 555 that is fluidically coupledthrough another tube (also not shown) to the inlet 556 of electrolysiscell 552.

Electrolysis cell 552 has an outlet 557 that is fluidically coupled tonozzle 508. In one example, electrolysis cell 552 corresponds to thetubular electrolysis cell 200 discussed with reference to FIG. 5.However, any suitable electrolysis cell can be used in alternativeembodiments, and the cell can have any shape and/or geometry. Forexample, the cell can have electrodes that are cylindrical as shown inFIG. 5 or substantially planar, parallel plates. O-ring 560 provides aseal about the nozzle 508 for housing 501.

Bottle 500′ further includes a trigger 570, which actuates a momentarypush-button on/off switch 572. Trigger 570 actuates about pivot 574 whendepressed by a user. A spring 576 (shown in FIG. 12C) biases trigger 570in a normally released state and thus switch 572 in an off state. Switch572 has electrical leads 578 for connecting to the control electronicson circuit board 540, shown in FIG. 10.

As described with reference to the block diagram shown in FIG. 7, whentrigger 570 is depressed, switch 572 actuates to the “on” state, therebyproviding electrical power to the control electronics, which energizespump 550 and electrolysis cell 552. When energized, pump 550 drawsliquid from container 510 and pumps the liquid through electrolysis cell552, which delivers a combined anolyte and catholyte EA liquid to nozzle508. When pump 550 and/or electrolysis cell 552 are functioningproperly, the control electronics also illuminate the liquid withincontainer 510 with the LEDs installed on the circuit board or anotherlocation in or on bottle 500′.

FIG. 13 illustrates bracket 554 in greater detail.

FIGS. 14A and 14B are perspective views of trigger 570. Trigger 570 hasa set of apertures 580 for receiving a pin or pins that define the pivotpoint of the trigger.

FIGS. 15A and 15B are perspective views of a trigger boot 584, whichoverlies trigger 570. Boot 584 provides a protective layer for trigger570 and seals the edges of housing 501 about the trigger.

FIG. 16A illustrates compartments 532 and 533 of housing half 501A ingreater detail. FIG. 16B illustrates the circuit board 540 mountedwithin compartment 532 and batteries 542 mounted within compartment 533.

In addition, circuit board 540 includes a plurality of light-emittingdiodes (LEDs) 594 and 596. In this example, the LEDs are positioned onthe top surface of circuit board 540 such that light radiating from theLEDs illuminates the liquid in container 510 through the base of thecontainer. Other arrangements can also be used. The LEDs can havedifferent colors and be controlled separately, as described above, toindicate different operating states or characteristics, for example.

12. Illumination Through the Liquid in Other Apparatus

The features and methods described herein, such as those of theelectrolysis cell and the indicator light(s), can be used in a varietyof different apparatus, such as on a spray bottle, a mobile surfacecleaner, and/or a free-standing or wall-mount electrolysis platform. Forexample, they can be implemented onboard (or off-board) a mobile surfacecleaner, such as a mobile hard floor surface cleaner, a mobile softfloor surface cleaner or a mobile surface cleaner that is adapted toclean both hard and soft floors or other surfaces, for example.

Field et al. U.S. Publication No. 2007/0186368 A1 discloses variousapparatus in which the features and methods described herein can beused, such as a mobile surface cleaner having a mobile body configuredto travel over a surface. The mobile body has a tank for containing acleaning liquid, such as tap water, a liquid dispenser and a flowpathfrom the tank to the liquid dispenser. An electrolysis cell is coupledin the flowpath. The electrolysis cell has an anode chamber and acathode chamber separated by an ion exchange membrane andelectrochemically activates tap water that has passed through thefunctional generator.

The functional generator converts the tap water into an anolyte EAliquid and a catholyte EA liquid. The anolyte EA liquid and thecatholyte EA liquid can be separately applied to the surface beingcleaned and/or sanitized, or can be combined on-board the apparatus toform a combination anolyte and catholyte EA liquid and dispensedtogether through a cleaning head, for example.

Field et al. U.S. Publication No. 2007/0186368 A1 also discloses otherstructures on which the various structural elements and processesdisclosed herein can be utilized either separately or together. Forexample, Field et al. disclose a wall mount platform for generatinganolyte and catholyte EA liquid.

Any of these apparatus can be configured to provide a visual indicationof a functional operating state or operating characteristic of theelectrolysis cell, wherein illumination of the indicator is visiblethrough the liquid from a viewpoint that is external to the apparatus.The indicator light is not required to be in a direct line of sight ofthe observer, but may be out of sight. For example, the illuminationmight be visible due to diffusion and/or diffraction of the light, suchas through the liquid.

In one example, a wall-mounted platform supports an electrolysis celland a liquid flow path from an inlet of the platform, through theelectrolysis cell, to an outlet of the platform. At least a portion ofthe flow path is at least translucent and visible from an exterior ofthe platform. The platform further includes an indicator light, such asthat shown in FIG. 7, that illuminates the liquid along at least aportion of the flow path, such as along a tube and/or a reservoir of theplatform.

13. Mobile Surface Cleaner

The features and methods described herein, such as those of theelectrolysis cell, can be used in a variety of different applications,such on a spray bottle, a mobile surface cleaner, and/or a free-standingor wall-mount electrolysis platform. For example, they can beimplemented onboard (or off-board) a mobile surface cleaner, such as amobile hard floor surface cleaner, a mobile soft floor surface cleaneror a mobile surface cleaner that is adapted to clean both hard and softfloors or other surfaces, for example.

Field et al. U.S. Publication No. 2007/0186368 A1 various apparatus inwhich the features and methods described herein can be used, such as amobile surface cleaner having a mobile body configured to travel over asurface. The mobile body has a tank for containing a cleaning liquid,such as tap water, a liquid dispenser and a flowpath from the tank tothe liquid dispenser. An electrolysis cell is coupled in the flowpath.The electrolysis cell has an anode chamber and a cathode chamberseparated by an ion exchange membrane and electrochemically activatestap water that has passed through the functional generator.

The functional generator converts the tap water into an anolyte EAliquid and a catholyte EA liquid. The anolyte EA liquid and thecatholyte EA liquid can be separately applied to the surface beingcleaned and/or sanitized, or can be combined on-board the apparatus toform a combination anolyte and catholyte EA liquid and dispensedtogether through a cleaning head, for example.

FIG. 17 illustrates an example of a mobile hard and/or soft floorsurface cleaner 700 disclosed in Field et al. U.S. Publication No.2007/0186368 A1 in which one or more of the above-described featuresand/or methods can be implemented. FIG. 17 is a perspective view ofcleaner 700 having its lid in an open position.

In this example, cleaner 700 is a walk-behind cleaner used to clean hardfloor surfaces, such as concrete, tile, vinyl, terrazzo, etc. in otherexamples, cleaner 700 can be configured as a ride-on, attachable, ortowed-behind cleaner for performing a cleaning and/or sanitizingoperation as described herein. In a further example, cleaner 700 can beadapted to clean soft floors, such as carpet, or both hard and softfloors in further embodiments. Cleaner 700 may include electrical motorspowered through an on-board power source, such as batteries, or throughan electrical cord. Alternatively, for example, an internal combustionengine system could be used either alone, or in combination with, theelectric motors.

Cleaner 700 generally includes a base 702 and a lid 704, which isattached along one side of the base 702 by hinges (not shown) so thatlid 704 can be pivoted up to provide access to the interior of base 702.Base 702 includes a tank 706 for containing a liquid or a primarycleaning and/or sanitizing liquid component (such as regular tap water)to be treated and applied to the floor surface duringcleaning/sanitizing operations. Alternatively, for example, the liquidcan be treated onboard or offboard cleaner 700 prior to containment intank 706. In addition, cleaner 700 includes an electrolysis cell 708,which treats the liquid prior to the liquid being applied to the floorbeing cleaned. The treated liquid can be applied to the floor directlyand/or through a cleaning head 710, for example. The treated liquid thatis applied to the floor can include an anolyte EA liquid stream, acatholyte EA liquid stream, both and anolyte and catholyte EA liquidstreams and/or a combined anolyte and catholyte EA liquid stream. Thecell 408 can include an ion selective membrane or be configured withoutan ion selective membrane.

Field et al. U.S. Publication No. 2007/0186368 A1 also discloses otherstructures on which the various structural elements and processesdisclosed herein can be utilized either separately or together. Forexample, Field et al. disclose a wall mount platform for generatinganolyte and catholyte EA liquid. This platform can be controlled with acontrol voltage pattern as disclosed herein, for example.

14. Wall-Mount Platform

For example, FIG. 18 illustrates a simplified block diagram of acleaning liquid generator 800 that is mounted to a platform 802according to an exemplary embodiment. Platform 802 can be configured tobe mounted or placed in a facility on a floor, a wall, a bench or othersurface, held by hand, carried by an operator or vehicle, attached on toanother device (such as carried by a cleaning or maintenance trolley ormop bucket), or carried on a person. In one specific embodiment,platform 802 is mounted to the wall of a facility for loading cleaningdevices, such as mop buckets, mobile cleaning machines, etc., withcleaning and/or sanitizing liquid.

Platform 802 includes an inlet 803 for receiving a liquid, such as tapwater, from a source. Alternatively, for example, platform 802 caninclude a tank for holding a supply of liquid to be treated. Platform802 further includes one or more electrolysis cells 804 and a controlcircuit 806 (such as those disclosed above). Electrolysis cell(s) 804can have any of the structures described herein or any other suitablestructure. Platform 802 can also include any other devices or componentssuch as but not limited to those disclosed herein.

The flow path or paths from the output of electrolysis cell 804 can beconfigured to dispense anolyte EA liquid and catholyte EA liquidseparately and/or blended anolyte and catholyte EA liquid through outlet808. Unused anolyte or catholyte can be directed to a waste tank onplatform 802 or to a drain outlet, for example. In embodiments in whichboth anolyte and catholyte EA are dispensed through outlet 808, theoutlet can have separate anolyte and catholyte ports and/or a combinedport, which delivers a blended mixture of catholyte and anolyte, forexample, as discussed above. Further, any of the embodiments herein caninclude one or more storage tanks for containing the anolyte and/orcatholyte produced liquid by the electrolysis cell.

In one specific embodiment, electrolysis cell 804 includes at least oneanode and at least one cathode that are separated by at least oneion-selective membrane, forming one or more anode chambers and cathodechambers. Outlet 808 has separate anolyte and catholyte ports, which arefluidically coupled to the anode chambers and cathode chambers,respectively, without any fluid valving, for example. The controlcircuit 806 energizes the anodes and cathodes with a voltage patterndiscussed above with reference to FIG. 6 such that each anolyte portsupplies a substantially constant anolyte EA liquid output, and eachcatholyte port supplies a substantially constant catholyte EA liquidoutput. A substantially constant, relatively positive voltage is appliedto the anodes, while a substantially constant, relatively negativevoltage is applied to the cathodes. Periodically each voltage is brieflypulsed to a relatively opposite polarity to repel scale deposits.

If the number of anode electrodes is different than the number ofcathode electrodes, e.g., a ratio of 3:2, or if the surface area of theanode electrode is different than the surface area of the cathodeelectrode, then the applied voltage pattern can be used in theabove-manner to produce a greater amount of either anolyte or catholyteto emphasize cleaning or sanitizing properties of the produced liquid.Other ratios can also be used. Platform 802 further can include a switchor other user input device 810, if desired, for operating the controlcircuit to selectively invert the voltage patterns applied to eachelectrode to produce a greater amount of anolyte or catholyte dependingupon the state of the switch.

15. All Surface Cleaner

FIG. 19 is a perspective view of an all surface cleaning assembly 980,which is described in more detail in U.S. Pat. No. 6,425,958, which isincorporated herein by reference in its entirety. The cleaning assembly980 is modified to include a liquid distribution path with one or moreelectrolysis cells with electrodes and a control circuit as describedherein such as but not limited to those shown or described withreference to FIG. 1, for example, or any of the other embodimentsdisclosed herein.

Cleaning assembly 980 can be constructed to deliver and optionallyrecover one or more of the following liquids, for example, to and fromthe floor being cleaned: anolyte EA water, catholyte EA water, blendedanolyte and catholyte EA water, or other electrically-charged liquids.For example, liquid other than or in addition to water can be used.

Cleaning assembly 980 can be used to clean hard surfaces in restrooms orany other room having at least one hard surface, for example. Cleaningassembly 980 includes the cleaning device and the accessories used withthe cleaning device for cleaning the surfaces, as described in U.S. Pat.No. 6,425,958. Cleaning assembly 980 includes a housing 981, a handle982, wheels 983, a drain hose 984 and various accessories. Theaccessories can include a floor brush 985 having a telescoping andextending handle 986, a first piece 987 and a second piece 988 of a twopiece double bend wand, and various additional accessories not shown inFIG. 19, including a vacuum hose, a blower hose, a sprayer hose, ablower hose nozzle, a spray gun, a squeegee floor tool attachment, agulper tool, and a tank fill hose (which can be coupled to ports onassembly 980). The assembly has a housing that carries a tank orremovable liquid container and a recovery tank or removable recoveryliquid container. The cleaning assembly 980 is used to clean surfaces byspraying the cleaning liquid through a sprayer hose and onto thesurfaces. The blower hose is then used to blow dry the surfaces and toblow the fluid on the surfaces in a predetermined direction. The vacuumhose is used to suction the fluid off of the surfaces and into therecovery tank within cleaning device 980, thereby cleaning the surfaces.The vacuum hose, blower hose, sprayer hose and other accessories usedwith cleaning assembly 980 can be carried with the cleaning device 980for easy transportation.

In addition, similar to the embodiment shown in FIGS. 8-16, any of theapparatus shown in or described with FIGS. 17-19 can include one or moreindicator lights 414 and/or 416 (shown in the block diagram of FIG. 7)positioned on the apparatus to illuminate the liquid itself, eitherprior to treatment by electrolysis cell 404 and/or after treatment. Forexample, the indicator light, when illuminated, generates luminous fluxin the visible wavelength range that is visually perceptible through theliquid from a viewpoint that is exterior to the apparatus. For example,the liquid may diffuse at least a portion of the light, giving a visualimpression that the liquid, itself, is illuminated. In one embodiment,the apparatus comprises a container, lumen or other element thatcontains the liquid and comprises a material and/or portion that is atleast translucent and positioned to transmit at least some of the lightproduced by indicator 414 and/or 416 when illuminated. This container,lumen or other element is at least partially visible from an exterior ofthe apparatus.

16. Control Circuit for Spray Bottle Shown in FIGS. 8-16

FIG. 20 is a block diagram illustrating a control circuit forcontrolling the various components within the hand-held spray bottles500, 500′ shown in FIGS. 8-16 according to an illustrative example ofthe disclosure. The main components of the control circuit include amicrocontroller 1000, a DC-to-DC converter 1004, and an output drivercircuit 1006.

Power to the various components is supplied by a battery pack 542carried by the bottle, as shown in FIG. 16B, for example. In a specificexample, battery pack 542 includes 10 nickel-metal hydride batteries,each having a nominal output voltage of about 1.2 Volts. The batteriesare connected in series, so the nominal output voltage is about 10V to12.5V with a capacity of about 1800 milliampere-hours. Hand trigger570,572 (shown in FIGS. 8A and 8B, for example) selectively applies the12-volt output voltage from battery pack 542 to voltage regulator 1003and to DC-to-DC converter 1004. Any suitable voltage regulator can beused, such as an LM7805 regulator from Fairchild SemiconductorCorporation. In a particular example, voltage regulator 1003 provides a5 Volt output voltage for powering the various electrical componentswithin the control circuit.

DC-to-DC converter 1004 generates an output voltage to be applied acrossthe electrodes of electrolysis cell 552. The converter is controlled bymicrocontroller to step the drive voltage up or down in order to achievea desired current draw through the electrolysis cell. In a particularexample, converter 1004 steps the voltage up or down between a range of8 Volts to 28 Volts (or greater) to achieve a current draw throughelectrolysis cell 552 of about 400 milliamps, as pump 550 pumps waterfrom container 510, through cell 552 and out nozzle 508 (FIGS. 8A and8B). The required voltage depends in part on the conductivity of thewater between the cell's electrodes.

In a particular example, DC-to-DC converter 1004 includes a Series A/SMsurface mount converter from PICO Electronics, Inc. of Pelham, N.Y.,U.S.A. In another example, converter 1004 includes an NCP3064 1.5AStep-Up/Down/Inverting Switching regulator from ON Semiconductor ofPhoenix, Ariz., U.S.A, connected in a boost application. Other circuitscan be used in alternative embodiments.

Output driver circuit 1006 selectively reverses the polarity of thedriving voltage applied to electrolysis cell 552 as a function of acontrol signal generated by microcontroller 1000. For example,microcontroller 1000 can be configured to alternate polarity in apredetermined pattern, such that shown and/or described with referenceto FIG. 6. Output driver 1006 can also provide an output voltage to pump550. Alternatively, for example, pump 550 can receive its output voltagedirectly from the output of trigger switch 570, 572.

In a particular example, output driver circuit 1006 includes a DRV 8800full bridge motor driver circuit available from Texas InstrumentsCorporation of Dallas, Tex., U.S.A. Other circuits can be used inalternative embodiments. The driver circuit 1006 has an H-switch thatdrives the output voltage to electrolysis cell 552 according to thevoltage pattern controlled by the microcontroller. The H-switch also hasa current sense output that can be used by the microcontroller to sensethe current drawn by cell 552. Sense resistor R_(SENSE) develops avoltage that is representative of the sensed current and is applied as afeedback voltage to microcontroller 1000. Microcontroller 1000 monitorsthe feedback voltage and controls converter 1004 to output a suitabledrive voltage to maintain a desired current draw.

Microcontroller 1000 also monitors the feedback voltage to verify thatelectrolysis cell 552 and/or pump 550 is operating properly. Asdiscussed above, microcontroller 1000 can operate LEDs 594 and 596 as afunction of the current levels sensed by output driver circuit 1006. Forexample, microcontroller 1000 can turn off (or alternatively, turn on)one or both of the sets of LEDs 594 and 596 as a function of whether thecurrent level sensed is above or below a threshold level or within arange.

In a particular embodiment, microcontroller 1000 can include anysuitable controller, such as an MC9S08SH4CTG-ND Microcontrolleravailable from Digi-Key Corporation of Thief River Falls, Minn., U.S.A.

In the example shown in FIG. 20, the illumination control portion of thecircuit includes output resistors R1 and R2 and a first, “red” LEDcontrol leg formed by pull-up resistor R3, red LED diodes D1-D4, andpull-down transistor Q1. Microcontroller 1000 has a first controloutput, which selectively turns on and off red LEDs D1-D4 by turning onand off transistor Q1. The illumination control portion of the circuitfurther a second, “green” LED control leg formed by pull-up resistor R4,green LED diodes D5-D8, and pull-down transistor Q2. Microcontroller1000 has a second control output, which selectively turns on and offgreen LEDs D5-D8 by turning on and off transistor Q2.

The control circuit further includes a control header 1002, whichprovides an input for reprogramming microcontroller 1000.

In one particular example, the elements 1000, 1002, 1003, 1004, 1006,R1-R4, D1-D8 and Q1-Q2 reside on circuit board 540, shown in FIG. 16B.

In addition, the control circuit shown in FIG. 20 can include a chargingcircuit (not shown) for charging the batteries within battery pack 542with energy received through the power jack 523 shown in FIG. 8C.

One or more of the control functions described herein can be implementedin hardware, software, firmware, etc., or a combination thereof. Suchsoftware, firmware, etc. is stored on a computer-readable medium, suchas a memory device. Any computer-readable memory device can be used,such as a disc drive, a solid state drive, flash memory, RAM, ROM, a setof registers on an integrated circuit, etc.

Although the present disclosure has been described with reference to oneor more embodiments, workers skilled in the art will recognize thatchanges may be made in form and detail without departing from the spiritand scope of the disclosure and/or the appended claims.

1. An electrolysis cell comprising: an anode electrode; and a cathodeelectrode, wherein at least one of the anode electrode and the cathodeelectrode are at least partially formed of conductive polymer.
 2. Theelectrolysis cell of claim 1 and further comprising an ion selectivemembrane disposed between the anode electrode and the cathode electrodeand which defines a respective anode chamber and cathode chamber.
 3. Theelectrolysis cell of claim 1, wherein both the anode electrode and thecathode electrode are at least partially formed of conductive polymer.4. The electrolysis cell of claim 1, wherein the anode electrode and thecathode electrode each consist solely of conductive polymer.
 5. Theelectrolysis cell of claim 1, wherein the conductive polymer has asurface resistivity of 10⁰ to 10¹² ohm/sq.
 6. The electrolysis cell ofclaim 1, wherein the conductive polymer has a surface resistivity of 10¹to 10⁶ ohm/sq.
 7. The electrolysis cell of claim 1, wherein the anodeelectrode and cathode electrode are cylindrical and are coaxial with oneanother.
 8. The electrolysis cell of claim 1 and further comprising: anion selective membrane disposed between the anode electrode and thecathode electrode and which defines a respective anode chamber andcathode chamber; an inlet, which directs a received liquid into theanode chamber and the cathode chamber; and an outlet, which receives acombined flow of liquid from the anode chamber and the cathode chamber.9. A mobile surface cleaner comprising the electrolysis cell of claim 1,a mobile body configured to travel over a surface; a source of a liquid;a liquid dispenser; and a flow path that passes from the liquid source,through the electrolysis cell, to the liquid dispenser.
 10. A hand-heldspray bottle comprising: a liquid reservoir; a liquid outlet; anelectrolysis cell carried by the bottle and fluidically coupled betweenthe reservoir and the liquid outlet, wherein the electrolysis cellcomprises an anode electrode and a cathode electrode, and wherein atleast one of the anode electrode or the cathode electrode is at leastpartially formed of conductive polymer; and a switch actuated betweenfirst and second states by a hand trigger, wherein the switch energizesthe electrolysis cell in the first state and de-energizes theelectrolysis cell in the second state.
 11. The hand-held spray bottle ofclaim 10 and further comprising: a power supply carried by the bottle,wherein the switch couples the electrolysis cell to the power supply inthe first state and de-couples the electrolysis cell from the powersupply in the second state.
 12. The hand-held spray bottle of claim 10and further comprising an ion selective membrane disposed between theanode electrode and the cathode electrode and which defines a respectiveanode chamber and cathode chamber.
 13. The hand-held spray bottle ofclaim 10, wherein the anode electrode and the cathode electrode eachconsist solely of conductive polymer.
 14. The hand-held spray bottle ofclaim 10, wherein the conductive polymer has a surface resistivity of10⁰ to 10¹² ohm/sq.
 15. The hand-held spray bottle of claim 10, whereinthe conductive polymer has a surface resistivity of 10¹ to 10⁶ ohm/sq.16. The hand-held spray bottle of claim 10, wherein the anode electrodeand cathode electrode are cylindrical and are coaxial with one another.17. The hand-held spray bottle of claim 10 and wherein the electrolysiscell further comprises: an ion selective membrane disposed between theanode electrode and the cathode electrode and which defines a respectiveanode chamber and cathode chamber; an inlet, which directs a receivedliquid into the anode chamber and the cathode chamber; and an outlet,which receives a combined flow of liquid from the anode chamber and thecathode chamber.
 18. A method comprising electrolyzing a liquid using anelectrolysis cell, which comprises at least one conductive polymerelectrode.
 19. The method of claim 18, wherein the method comprises:introducing a first part of the liquid into a first electrolysis chambercomprising a first electrode; introducing a second part of the liquidinto a second electrolysis chamber comprising a second electrode,wherein the second electrolysis chamber is separated from the firstelectrolysis chamber by an ion selective membrane and wherein at leastone of the first or second electrodes comprises a conductive polymer;and applying a voltage across the first and second electrodes toelectrochemically activate the first and second parts of the liquid.